Internal-combustion engine



D. V. BOUREAU. INTERNAL COMBUSTION ENGINE.

APPLICATION FILED APR. 30, 1,917-

Patented May 10, 1921.

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APPLICATION FILED APR. 30. 19!?- 1,377,66 1. Patented May 10,1921.

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D. V. BOUREAU.

. INTERNAL COMBUSTION ENGINE. APPLICATION FILED APR. 30. .191

1,377,661. 7 Patented May 19,1921.

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PATENT orrlca.

DESIRE V. BOUREA'U, F BROOKLYN, N EXV YORK.

INTERNAL-COMBUSTION ENGINE.

Specification of Letters Patent.

Patented May 10, 1921.

Application filed. April 30, 1917. Serial No. 165,558.

To all whom it may concern:

Be it known that I Dnsinn V. BoURnAU, a citizen of the French Republic, resldlng at Brooklyn,' in the county of Kings and State specification.

This invention relates to improvements in internal combustion engines and particularly to improvements in enginesof the twostroke cycle type in which the explosive mixture is preliminarily compressed before being admitted to the combustion chamber.

The object of this invention is to provide a very powerful and efiicient motor of the two-stroke cycle type which is especially fitted for heavy duty and which is adapted to operate efficiently on kerosene and low grade hydrocarbons. A further object of my invention is to provide a two cycle engine in which the cylinder is closed at top and bottom and the explosive mixture is compressed in the lower part of the cylinder bythe piston before being admitted to the combustion chamber in the upper part of one of the other cylinders.

Further objects, and objects relating to economies of operation and details of construction, will definitely appear from the detailed description to follow.

I accomplish the objects of my invention by the devices and means described in the following specification. My invention is clearly defined and pointed out in the claims.

A structure constituting a preferred embodiment of my invention is illustrated in the accompanying drawings forming a part ofthis specification, in which:

Figure I is a vertical sectional view through an engine constructed in accordance with my invention.

Fig. II is a view of my engine in side elevation, the side of the crank case being broken away.

Fig. III is a vertical sectional view through the cylinder with the piston at lower dead center.

Fig. IV is a similar view showing the position of the piston and the piston valve at the beginningof the intake into the combustion chamber. I

Fig. V is a transverse sectional View taken. .Qll linefiee of Fig. I,

Fig. VI is a transverse sectional view taken on the line 66 of Fig. I.

Fig. VII is a transverse sectional View taken on the line 7-7 of Fig. I.

In the drawings, similar reference characters refer to similar parts throughout the several views and the sectional views are taken looking in the direction of the little arrows at the end of the section lines.

In carrying out the object of my invention I provide an engine comprising a plurality of cylinders having shown four in the present case. each cylinder being closed at top and bottom and having'a piston working therein with the space above the piston forming a combustion chamber and the space below the piston forming a pre-compression chamber. The ports through which the gas or explosive mixture enters and leaves these chambers are controlled by a piston valve moving parallel to the piston and making one complete strpke for each complete stroke of the piston, said piston valve being so timed as to permit the intake of gas at the proper instant in the stroke of the piston. During the upstroke of the piston gas is drawn from the carbureter or similar device for supplying explosive mixture into the pre-compression space below the piston and during the downstroke of the piston is compressed and forced out into the combustion chamber of another cylinder which at that instant is taking a fresh charge of gas.

Considering the numbered parts of the drawing my improved engine comprises a plurality of cylinders 1, preferably four or a multiple thereof, mounted on the upper half of the crank case which comprises the upper part 2 and the lower half 8 said halves of the crank case being provided with the laterally projecting flanges 4 by means of which they are secured together. The top of the cylinder is closed by means of the removable cylinder head 5 which is secured in place by means of the bolt 6 and is provided with an opening 6' to receive a spark plug. The lower end of the cylinder is closed by means of the wall 7 which is preferably formed integral with the cylinder wall and the upper half of the crank case. A central opening 8 is formed in said wall and provided with a stuffing box 9 through which passes the rod 10 haying a t pe ed up per end 10 to which the piston 11 is socured by means of the nut 12. The piston and the rod 10 reciprocate within the cylinder in the usual manner.

I preferably provide my piston with a central core 37 having a tapered bore in which the tapered end 10 of the rod 10 is disposed. Walls 38 radiate from this cen tral core and carry the external shell 39 of the piston which is provided with the usual piston ring. The head of the piston is, of course, solid. The piston is provided also with a depending skirt 13 as shown in Figs.

.11, III and IV of the drawings.

In the upper part of the crank case below the wall 7 is formed a cylindrical bore 1 1 in which the cylindrical block 15 secured to the lower end of the rod 10 reciprocates. This block 15 is connected to the upper end of the piston rod 16 the lower end of which is connected to the one arm 17 of the crank shaft 18 which is suitably journaled in the crank case. The arms of the crank shaft extend at angles of ninety degrees from each other.

A piston valve casing 19 is provided for each cylinder extending parallel thereto and preferably integral therewith. This'casing has a cylindrical bore in which the piston valve 20 reciprocates and it is provided with a small vent 21 at the upper end thereof. The lower end of the piston valve is connected by means of the rod 22 with the corresponding arm 23 of the counter-crankshaft 24 having arms corresponding to arms of the crank shaft and being suitably journaled in the crank case. The counter-crankshaft is operatively connected with the crank shaft by means of the intermediate gearing 25 so that the counter-crank-shafts make a complete revolution for each revolution of the crank shaft. 7

The valve casing 19 is provided with a lower intake 26 which is connected with the carbureter or similar device for generating and supplying an explosive mixture and the boreof the valve casing is connected with the pre-compression space below the piston in the cylinder 1 by means of an intake port 27 opposite the intake port 26. distance above the intake 26 there is provided an outlet port 28 and the pre-compression space of the cylinder is connected with the bore of the valve casing by means of the inclined port 29 which merges into the intake port 27. The valve casing is provided with an upper intake port 30 and the bore of the vided in the cylinder wall which port is com paratively wide so as to permit of the more ready scavenging of the combustion chamber. The exhaust port 32 hasa central par- A slight tition 32 to help hold the piston rings in place. The piston valve has a lower port 34: which is adapted to connect port 26 with port 27, a central inclined port 35 which is adapted to connect port 28 with port 29 and an upper port 36 which connects port 30 with port 31. In order to make this description clear I have indicated the cylinders of the engine by the letters A, B, C, and D, although the cylinders are identical in construction. The cylinders fire in the order A, B, D, C. Port 28 of each valve easing is connected with port 30 of the valve casing corresponding to another cylinder by means of a pipe or tube 33. As shown in Fig. I of the drawings port 28 of cylinder A is connected with port 30 of cylinder C, port 28 of cylinder B is connected with port 30 of cylinder A, port 28 of cylinder C is connected with port 30 of cylinder D, and port 28 of cylinder D is connected with port 30 of cylinder B.

From the description of the parts given above the operation of my engine should be i very readily understood. WVhen the piston is at lower dead center and begins its upstroke the piston valve 20 has moved to such a position that the port 3 1 is in line with ports 26 and 27 and gas is drawn into the compression space below the piston from the carbureter. As the piston moves up it first closes the exhaust port 32 and at the instant when the exhaust port-is closed the piston valve has moved so that the upper port 36 is in line with ports 30 and 31 and a charge of gas which has been compressed to a certain extent in the pre-compression space of the. cylinder with which the port 30 is connected, enters the combustion chamber. As the piston moves up it closes the port 31 and the charge is further compressed during the rest of the upstroke ofthe piston. The explosion takes place at or near upper dead center and the piston moves down under the impetus givento it by the explosion compressing the charge which-has been drawn into the pre-compression space belowthe piston. WVhen the piston reaches the lower limits of its stroke it opens exhaust port 32 thus permitting the burnt gases to pass out from the combustion chamber. The combustion chamber intake port is not open until the piston starts on its upward movement so that it is not open while the scavenging is taking place and none'of the fresh charge passes out through the exhaust port.

I have shown my invention as embodied in an engine comprising four cylinders, but it will be evident that it is not limited to this number of cylinders butmay be applied and worked out in an engine having two or more cylinders.

I- am: aware that the particular embodiment of my invention hereshown and described is'susceptible of considerable variation without departing from the spirit thereof, and therefore I desire to claim the same broadly as indicated by the appended claims. I I

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is: l

1. In an internal combustion engine, the combination of a crank shaft and a plurality of cylinders provided with gas explosion and pre-compression chambers, a piston in each of said cylinders connected with said crank shaft, a laterally positioned valve casing for each of said cylinders, a slide valve in each of said casings, each having three transverse passageways, one of which is adapted to communicate with the explosion chamberof one cylinder, and the other two adapted to alternately register with an inlet port leading to the pre-compression chamber of said cylinder for admitting and exhausting gas to and from the same, said last mentioned transverse passage-ways being adapted to alternately communicate with intake and outlet passageways through the outer wall of the valve casing, the latter passageway communicating with the combustion chamber of another cylinder through the first-mentioned transverse passage-way in the valve thereof and valve casing therefor, and a crank shaft for actuating said piston valves.

2. In an internal combustion engine, the combination of a crank shaft and a plurality of cylinders provided with gas explosion and pre-compression chambers, a piston in each of said cylinders connected with said crank shaft and movable between said chambers, a valve casing at one side of each of said cylinders having inlet ports through its outer wall opposite inlet ports through the cylinder wall leading to said explosion and pre-compression chambers and an intermediate port through its outer wall communicating with one of the inlet ports of the combustion chamber of another cylinder casing for supplying fuel to the explosion chamber thereof, a slide valve in each of said casings having a transverse passage way therethrough adapted to register with the ports in said casing and cylinder wall opposite the explosion chamber, said valve having two other transverse passageways, one of which simultaneously registers with said intermediate port and the port in the cylinder wall leading to the pre-compression chamber, and the other adapted to establish communication between the last mentioned port and the intake port opposite thereto in the outer wall of the valve casing and actuating means for said slide valve.

3. In an internal combustion engine, the combination of a plurality of cylinders having alined precompression and combustion chambers, a piston working in each cylinder, a crank-shaft driven by said pistons, a valve casing for each cylinder, a piston .valve working in each valve casing, a counter crankshaft driven by said crank-shaft, connecting rods connecting said piston valves with the crank-arms of said counter crankshaft, each of said precompression cham hers being provided with an intake port and each of said valve casings being provided with a lower intake port coacting therewith and connected with a supply of explosive mixture, each of said piston valves being provided with a lowerport coacting with said intake ports to permit-the passage of successive charges into said, precompression chamber at predetermined intervals, each of said combustion chambers being provided with an intake port disposed so as to be closed by the piston near the beginning of its up-stroke and each of said valve casings having an upper intake port coacting therewith, each ofsaid piston valves having an upper port coacting with said last named intake ports to permit the passage of successive charges from said precompression chambers into said combustion chambers, each of said precompression chambers having an exhaust port, pipes connecting each of said exhaust ports with the upper intake port of the valve casing of an adjacent cylinder, and exhaust ports for said combustion chambers.

4. In an internal combustion engine, the combination of a plurality of cylinders having alined precompression and combustion chambers, a piston working in each cylinder, a crankshaft driven by said pistons, a valve casing for each cylinder, a piston valve working in each valve casing, means, actuated by said crank-shaftfor driving said piston valves, each of said precompression chambers being provided with an intake port and each of said valve casings having a lower intake port coacting therewith and connected with a supply of explosive mixture, each of said piston valves having a lower port coacting with said intake ports to per mit the passage of successive charges into said precompression chambers at predetermined intervals, each of said combustion chambers having an intake port disposed so as to be closed by the piston near the beginning of its up-stroke, and each of said valve casings having an upper intake port coacting therewith, each of said piston valves having an upper port coacting with said last-named intake ports to permit the passage of successive charges from said precompression chambers into said combustion chambers, each of said precompression chambers having an exhaust port, pipes connecting each of said exhaust ports with the upper intake ort of the valve casing of an said combustion chambers.

Cir

5. In an internal combustion engine, the combination of a plurality of cylinders having alined precompression and combustion chambers, a piston working in each cylinder, a valve ca'singfor each cylinder having a lower intake port connected with a chargeforming device, a slide valve working in each valve casing and having a lower port adapted to connect the said intake port with the intake port of the corresponding precompression chamber at predetermined intervals, an exhaust port for each precompression chamber, an upper intake port in each valve casing, connections between each of said exhaust ports and the upper intake port of the valve casing of an adjacent cylinder, an intake port for each combustion chamber disposed so as to be closed by the piston near the beginning of its upstroke, an upper port in said slide valve adapted to connect the upper intake port of the valve casing with the intake port of the combustion chamber, an exhaust port for each combustion chamber disposed so as to be closed by the piston at the beginning of its upstroke, and means for actuating said slide valves.

'6. In an internal combustion engine of the two-stroke cycle type, the combination of a plurality of cylinders provided with alined precompression and combustion chambers, a piston Working in each cylinder, said precompression chambers being provided with intake and exhaust ports and said combustion chambers being provided with exhaust ports disposed so as to be closed by the piston at the beginning of the up-stroke and intake ports disposed just above the exhaust ports so as to be closed by the piston near the beginning of the up-stroke, a valve casing for each cylinder provided with a lower intake port connected with a charge-forming device and an upper intake'port connected with the exhaust port of the precompression chamber of an adjacent cylinder, a slide valve working in each casing and provided with upper and lower ports adapted to connect said upper intake port with the'intake port of the combustion chamber and said lower intake port with the intake port of the precompression chamber, and means for actuating said slide valves.

In witness whereof, I have hereunto set my hand and seal. I I

DESIRE VpBOUREAU. [L. s.] 

